This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. SPECIFIC AIMS: The overarching goal of the research is to identify biosocial mechanisms that contribute to the health benefits of social support. [unreadable] Examine the dynamic biopsychosocial processes that give rise to social responses to external threats. [unreadable] Examine gender differences in these processes with a focus on potential sex differences in underlying biological processes. [unreadable] Clarify the mechanisms by which social relationships beneficially or adversely affect biological, psychological, and social responses to threat. More specifically, we will: [unreadable] Examine the psychological and social correlates of natural elevations in OT in order to replicate and extend our previous findings that plasma OT is elevated in conjunction with gaps and problems in social relationships. [unreadable] Determine if elevated OT acts as an impetus to seek affiliative contact. [unreadable] Examine whether elevated OT leads to reduced autonomic and HPA axis responses to stress in conjunction with positive social contacts. [unreadable] Examine whether elevated OT leads to enhanced autonomic and HPA stress responses to stress in conjunction with unsupportive social contacts. [unreadable] Examine whether these processes occur in men as well as women and investigate whether vasopressin (AVP), a neuropeptide very similar to OT, may be implicated in men's social responses to stress.